This patent application claims a priority on a Japanese patent application, 2000-207745 filed on Jul. 10, 2000, the contents of which are incorporated herein by reference.
1. Field of the Invention
The present invention relates to an IC device, a circuit board and an IC assembly. More particularly, the present invention relates to an IC device, a circuit board and an IC assembly that allow a battery cell to be mounted on the circuit board in such a manner that the battery cell and the IC device are arranged in a direction perpendicular to the circuit board.
2. Description of the Related Art
In recent years, portable devices, such as camera and a mobile phone, have been developed significantly, so as to have multiple functions. In order to realize the multiple functions, it is necessary to mount a plurality of electric devices and circuits onto a circuit board.
The electric devices to be mounted on the circuit board include an integrated circuit (IC) and a battery cell, for example. These electric devices, however, occupy a relatively large area of the circuit board, thus preventing the size reduction of the portable devices.
In order to realize the small portable devices having multiple functions, it is necessary to efficiently use a limited space on the circuit board. Therefore, it is an object of the present invention to provide an IC device, a circuit board and an IC assembly, which are capable of overcoming the above drawbacks accompanying the conventional art. The above and other objects can be achieved by combinations described in the independent claims. The dependent claims define further advantageous and exemplary combinations of the present invention.
According to the first aspect of the present invention, an IC device for use with a battery cell, comprises: an IC operable to be mounted on a circuit board; a plurality of connecting terminals, extending from the IC, operable to fix the IC to the circuit board; and a plurality of electrode-connecting terminals operable to connect the battery cell to the circuit board when the battery cell is mounted on the circuit board in such a manner that one of the battery cell and the IC overlaps the other in a direction substantially perpendicular to the circuit board.
Parts of the plurality of connecting terminals may serve as the electrode-connecting terminals.
The IC device may include a controller operable to control power supply from the battery cell.
According to the second aspect of the present invention, a circuit board for use with an IC device and a battery cell, comprises: a first surface onto which the IC device is to be mounted; a second surface opposite to the first surface; and a plurality of electrode-connecting terminals operable to connect the battery cell to the circuit board when the battery cell is mounted on the circuit board in such a manner that one of the IC device and the battery cell overlaps the other in a direction substantially perpendicular to the circuit board.
The battery cell may be mounted on the first surface to be positioned on the IC device.
Alternatively, the battery cell may be mounted on the second surface, and the electrode-connecting terminals are provided on the second surface.
In this case, the circuit board may further comprise a battery accommodating portion operable to accommodate at least a part of the battery cell, that is formed in the second surface. The battery accommodating portion may be a dent formed in the second surface.
According to the third aspect of the present invention, an IC assembly comprises: a circuit board; an IC device mounted on the circuit board, the IC device including an IC placed on the circuit board and a plurality of connecting terminals operable to fix the IC onto the circuit board; and a battery cell mounted on the circuit board in such a manner that one of the IC device and the battery cell overlaps the other in a direction substantially perpendicular to the circuit board, wherein a plurality of electrode-connecting terminals are provided to connect the battery cell to the circuit board.
The battery cell may be placed on the IC of the IC device. In this case, parts of the plurality of connecting terminals of the IC device may serve as the electrode-connecting terminals. Alternatively, the electrode-connecting terminals maybe provided separately from the connecting terminals.
The circuit board may include a first surface on which the IC device is mounted and a second surface opposite to the first surface, while the battery cell maybe mounted on the second surface and the electrode-connecting terminals are provided on the second surface.
The battery cell may be mounted on the second surface to be overlapped by the IC device.
The second surface of the circuit board may have a battery accommodating portion operable to accommodate at least a part of the battery cell therein. The battery accommodating portion may be an opening passing from the second surface to the first surface. Alternatively, the battery accommodating portion may be a dent formed in the second surface.
The battery cell may be a battery cell for backup of a device into which the IC assembly is incorporated. In this case, the IC device may have at least a function of controlling power supply from the battery cell to the device. Moreover, the battery cell may be chargeable, while the IC device may have at least a function of controlling charging of the battery cell.
The summary of the invention does not necessarily describe all necessary features of the present invention. The present invention may also be a sub-combination of the features described above. The above and other features and advantages of the present invention will become more apparent from the following description of the embodiments taken in conjunction with the accompanying drawings.